Subzero: Run sandboxed cross tests, and do some cleanup.

src/assembler_ia32.h

Index: src/assembler_ia32.h
diff --git a/src/assembler_ia32.h b/src/assembler_ia32.h
index 06a601eb0d4296e27b320598454aeb087a0fe00e..a6a0bb4da651bf65ac7756a8c3de3243ed398c8f 100644
--- a/src/assembler_ia32.h
+++ b/src/assembler_ia32.h
@@ -803,16 +803,11 @@ public:
   void mfence();
 
   void lock();
-  void cmpxchg(Type Ty, const Address &address, GPRRegister reg);
-  void cmpxchg8b(const Address &address);
-  void xadd(Type Ty, const Address &address, GPRRegister reg);
+  void cmpxchg(Type Ty, const Address &address, GPRRegister reg, bool Locked);
+  void cmpxchg8b(const Address &address, bool Locked);
+  void xadd(Type Ty, const Address &address, GPRRegister reg, bool Locked);
   void xchg(Type Ty, const Address &address, GPRRegister reg);
 
-  void LockCmpxchg(Type Ty, const Address &address, GPRRegister reg) {
-    lock();
-    cmpxchg(Ty, address, reg);
-  }
-
   void EmitSegmentOverride(uint8_t prefix);
 
   intptr_t PreferredLoopAlignment() { return 16; }